2022-01-12 09:42:00

by Wayne Chang

Subject: [PATCH v5 1/1] ucsi_ccg: Check DEV_INT bit only when starting CCG4

From: Sing-Han Chen <[email protected]>

CCGx clears Bit 0:Device Interrupt in the INTR_REG
if CCGx is reset successfully. However, there might
be a chance that other bits in INTR_REG are not
cleared due to internal data queued in PPM. This case
misleads the driver that CCGx reset failed.

The commit checks bit 0 in INTR_REG and ignores other
bits. The ucsi driver would reset PPM later.

Fixes: 247c554a14aa ("usb: typec: ucsi: add support for Cypress CCGx")
Cc: [email protected]
Signed-off-by: Sing-Han Chen <[email protected]>
Signed-off-by: Wayne Chang <[email protected]>
---
V4 -> V5: Added Cc tag and revised the commit messages
V3 -> V4: Updated the Fixes tag
V2 -> V3: Added the Fixes tag
V1 -> V2: Fixed the name of Sign-off-by
drivers/usb/typec/ucsi/ucsi_ccg.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/usb/typec/ucsi/ucsi_ccg.c b/drivers/usb/typec/ucsi/ucsi_ccg.c
index bff96d64dddf..6db7c8ddd51c 100644
--- a/drivers/usb/typec/ucsi/ucsi_ccg.c
+++ b/drivers/usb/typec/ucsi/ucsi_ccg.c
@@ -325,7 +325,7 @@ static int ucsi_ccg_init(struct ucsi_ccg *uc)
if (status < 0)
return status;

- if (!data)
+ if (!(data & DEV_INT))
return 0;

status = ccg_write(uc, CCGX_RAB_INTR_REG, &data, sizeof(data));
--
2.25.1

2022-01-12 11:06:06

by Heikki Krogerus

Subject: Re: [PATCH v5 1/1] ucsi_ccg: Check DEV_INT bit only when starting CCG4

On Wed, Jan 12, 2022 at 05:41:43PM +0800, Wayne Chang wrote:
> From: Sing-Han Chen <[email protected]>
>
> CCGx clears Bit 0:Device Interrupt in the INTR_REG
> if CCGx is reset successfully. However, there might
> be a chance that other bits in INTR_REG are not
> cleared due to internal data queued in PPM. This case
> misleads the driver that CCGx reset failed.
>
> The commit checks bit 0 in INTR_REG and ignores other
> bits. The ucsi driver would reset PPM later.
>
> Fixes: 247c554a14aa ("usb: typec: ucsi: add support for Cypress CCGx")
> Cc: [email protected]
> Signed-off-by: Sing-Han Chen <[email protected]>
> Signed-off-by: Wayne Chang <[email protected]>

Reviewed-by: Heikki Krogerus <[email protected]>

> ---
> V4 -> V5: Added Cc tag and revised the commit messages
> V3 -> V4: Updated the Fixes tag
> V2 -> V3: Added the Fixes tag
> V1 -> V2: Fixed the name of Sign-off-by
> drivers/usb/typec/ucsi/ucsi_ccg.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/usb/typec/ucsi/ucsi_ccg.c b/drivers/usb/typec/ucsi/ucsi_ccg.c
> index bff96d64dddf..6db7c8ddd51c 100644
> --- a/drivers/usb/typec/ucsi/ucsi_ccg.c
> +++ b/drivers/usb/typec/ucsi/ucsi_ccg.c
> @@ -325,7 +325,7 @@ static int ucsi_ccg_init(struct ucsi_ccg *uc)
> if (status < 0)
> return status;
>
> - if (!data)
> + if (!(data & DEV_INT))
> return 0;
>
> status = ccg_write(uc, CCGX_RAB_INTR_REG, &data, sizeof(data));
> --
> 2.25.1

thanks,

--
heikki